Search Results (5)

This study was performed on the territory of Northern Europe in the Middle taiga subzone of Karelia. The work was conducted at two test sites (Site I, Site II) located in a pine forest in the coastal area of Lake Segozero. In these territories, areas under juniper (UCB) and under lingonberry-blueberry plant microgroups (CB) were isolated. This article presents the results of the effect of juniper on the properties of the upper soil horizon, forest litter (O), and mineral podzolic horizon (E (UCB)). The forest floor (O), and the mineral podzolic horizon (E) of soils located under the lingonberry-blueberry plant microgroup (CB) were selected as controls. The volume weight; acidity; content of total C, total N, total K, and total P had differences in different horizons (O, E) of the soils at the studied sites (Site I, Site II; CB, UCB). The results showed a tendency for C and N reserves to increase in the upper soil horizon under juniper. K and P reserves in this soil horizon tended to decrease. An increase in catalase activity was found in soils under juniper (Site I, II—UCB), which indicates a change in redox conditions. An increase in the rate of cellulose decomposition was noted in UCB sites compared with CB, which is consistent with the results of other studies. Mathematical and statistical analysis confirmed the formation of vegetative microgroups (CB and UCB) in cranberry pine (Site I, Site II) and also allowed us to identify conjugate pairs of chemical parameters (nitrogen reserves, C, catalase activity, and cellulose-destroying ability of soils) that differ in these sites. Full article

The intensive use, development, and expansion of the road network is expanding the zones of direct impact of road transport on forest ecosystems. Issues related to the mobility of trace elements in forest ecosystems along motorways are very important due to the numerous environmental risks associated with the excessive accumulation of metals, the ability to migrate and accumulate in plants and animals, and the risk of transferring these elements to higher trophic levels. The aim of this article was therefore to determine the impact of road traffic on the basis of contents of trace metals Cd, Cr, Cu, Ni, Pb, and Zn and to describe the relationship of these contents in moss gametophytes and blueberry leaves taken in the vicinity of an existing and variously expanded expressway (S7, Poland, Europe). Analyses of transport impacts included the effects of distance and time of pollutant deposition and road transport on habitat and stand conditions. The highest contents of Cd, Cr, Cu, Ni, Pb, and Zn in moss tissues were found in fir stands and the contents were, respectively, 0.36 mg·kg⁻¹, 5.91 mg·kg⁻¹, 12.5 mg·kg⁻¹, 3.26 mg·kg⁻¹, 8.82 mg·kg⁻¹, and 55.28 mg·kg⁻¹. Mosses showed the best bioindication capacity of all of the studied ecosystem elements. The Pb, Zn, Cr, Cu, and Ni contents were particularly markedly elevated in moss tissues relative to non-anthropopressured areas and dependent on distance from the emitter (road). Blueberry proved to be a less useful bioindicator, as the contents of Cd, Cr, Cu, Ni, Pb, and Zn found were similar to the data from non-anthropopressured areas and were, respectively, 0.09 mg·kg⁻¹, 0.98 mg·kg⁻¹, 7.12 mg·kg⁻¹, 2.49 mg·kg⁻¹, 1.18 mg·kg⁻¹, and 15.91 mg·kg⁻¹ in fir stands and 0.04 mg·kg⁻¹, 0.47 mg·kg⁻¹, 6.63 mg·kg⁻¹, 1.65 mg·kg⁻¹, 0.72 mg·kg⁻¹, and 17.44 mg·kg⁻¹ in pine stands. Full article

Currently, there is no consensus on how growing conditions affect the heartwood formation in Scots pine. Comparing the results obtained by different authors is difficult due to methodology differences and poor descriptions of the objects used. We selected two sample plots in (1) a blueberry pine forest on nutrient-rich and moist soil and (2) a lichen pine forest on nutrient-poor and dry soil and performed their detailed characterization. The sample plots were located 22 km apart in the middle taiga subzone (Karelia Republic, northwest Russia). In each sample plot, we selected five dominant trees (model trees), from which we took cores at different trunk heights (0.3, 1.5, 4.5, 7.5 and 10.5 m). The cores were treated with 2,6-dichlorophenolindophenol to identify the heartwood zone. Additionally, samples were taken to study the structural features of the transition zone between sapwood and heartwood. In both forest types, the number of heartwood rings depended on the cambium age, and the patterns of parenchyma cell death did not differ in the transition zone. These facts point to a predominantly internal regulation of the heartwood formation in Scots pine. The heartwood radius and its proportion on the cross-sections were significantly higher in the blueberry pine forest than in the lichen pine forest, despite the relative values of the annual ring width. Further research is needed to develop successful Scots pine heartwood width models under a wide range of conditions. Full article

Systematic assessments on the effects of skidding systems on features of forest blueberry pine soil were conducted as part of this study. Assessing the ecological efficiency of forest skidding machines showed that the most significant impact (by 2.0–2.2 times) on soil compaction was observed at loading sites rather than during transportation. Lightweight loam density and sand density increased by 25% and 2%, respectively, after more than two passages of the skidding system. Pressure in 33L-32 tires of forestry machinery in operation on a solid surface varied from 46.5 kPa to 196 kPa at maximum load. Studying the impact of tires on soil compaction showed that the environmental efficiency of forestry equipment can be enhanced if the optimal tire pressure at average loads does not exceed 70 kPa for tracked vehicles and 150 kPa for wheeled vehicles in summer seasons. When ground grips were fully immersed, the pressure of forwarders on soil was reduced. These study results can be used to establish organizational and technological measures in order to manage the negative impact of skidding systems and to increase the environmental effects of their performance. Full article

There is limited information on how velvet leaf blueberry (Vaccinium myrtilloides Michx.) responds to fires and existing small forest gaps associated with narrow linear disturbances. We measured the effects of narrow forest linear gaps from seismic lines used for oil and gas exploration versus adjacent (control) forests across a fire severity (% tree mortality) gradient on the presence, abundance (cover), vigor (height), and berry production of Vaccinium myrtilloides in recently (five-year) burned jack pine (Pinus banksiana Lamb.) forests near Fort McMurray, Alberta. Presence was greatest in forests that experienced low to moderately-high fire severities with declines at high fire severity. Abundance did not differ among seismic lines or adjacent forest, nor did it differ along a fire severity gradient. In contrast, vigor and berry production were greater on seismic lines compared to adjacent forests with fire severity positively affecting berry production, but not plant vigor. After controlling for changes in plant cover and vigor, berry production still increased with fire severity and within seismic lines compared with adjacent forests. Our findings suggest that narrow gaps from linear disturbances and fire severity interact to affect the fecundity (berry production) and growth (height) of Vaccinium myrtilloides. This has important implications for assessing the ecological effects of fire on linear disturbances associated with energy exploration in the western boreal forest. Full article